While a conventional rotary electric machine such as a DC motor used crossover wirings as connection means for electrically connecting the winding terminals of the respective stator coils thereof, a printed circuit board or a single pressed metal plate in place of the crossover wirings has been used so as to facilitate the connection work of winding terminals and to prevent a break in the connection portions of the winding terminals when the stator is molded.
FIGS. 1(a) to (c) are developed perspective views to show the coil winding portions of stator coils in conventional DC motors in which winding patterns are different.
In the drawings, a reference numeral 1 denotes an annular yoke; a reference numeral 2 denotes a plurality of teeth disposed on the inner peripheral surface of the yoke 1; a reference numeral 3 denotes a terminal, and a reference numeral 4 denotes windings wound around the above mentioned respective teeth 2 to constitute a plurality of stator coils. The terminal portions of these windings 4 are connected to the respective stator coils by crossover wirings (not shown) to constitute the stators and the stators are molded with resin. Here, in FIGS. 1(a), (b), the windings 4 wound around the teeth 2 constitute three-phase stator coils of U-phase, V-phase, and W-phase, and in FIG. 1(c), the terminal 3 is constituted by two terminals 3a, 3b for one tooth 2. Here, in FIG. 1(a), a reference numeral 5 denotes a common wire-wound portion.
Because the winding termination portion of the conventional rotary electric machine is constituted in the manner described above, there is presented a problem that many malfunctions of breaks in the above mentioned crossover wirings are caused by a molding pressure when a stator is molded in a state where the terminals of the windings 4 wound around the respective teeth 2 are connected to the respective stator coils by crossover wirings. Further, connecting the terminals of many windings 4 wound around the respective teeth 2 respectively by the crossover wirings to stator coils, as described above, presents a problem of making the connection work troublesome and thus reducing workability. Still further, there is presented a problem that forming common wirings by an automated machine makes winding processes increased for additional terminals and common wire-wound.
For this reason, in the conventional rotary electric machine, a printed circuit board or a single conducting pressed metal plate has been used as a current passing unit to simplify a winding termination process.
In a case of the printed circuit board, however, there is presented a problem that while a device can be mounted thereon, a spring (plate spring) of a motor brush for contact can not be welded thereto thereby it causes not only reducing flexibility but also increasing manufacturing cost. Further, there is presented another problem that in order to mount a noise removing device such as a capacitor, a resistor or the like, a mounting board thereof heeds to be mounted thereon as a separate component.
On the other hand, in a case of the single pressed metal plate, there are presented the following problems: constituting a complex current passing pattern requires a plurality of metal plates, which results in increasing a number of components and making the work of mounting them troublesome and increasing manufacturing cost; and, in general, a pressed metal plate used as this kind of current passing means is a thin plate, so that in a case where a single plate is used, in particular, its strength is not sufficient.
The present invention has been made to solve the above mentioned problems. It is the object of the present invention to provide a current passing circuit board of a rotary electric machine in which a plurality of wiring patterns that are complex and are to be electrically isolated from each other can be formed of a one metal plate and at the same time it eliminates the need for using a crossover wiring to thereby make a winding termination process easy, and it is easy to manufacture and can reduce the number of components and can reduce the manufacturing cost.
Further, it is also the object of the present invention to provide a current passing circuit board of a rotary electric machine on which a noise removing device and brush for contact can be mounted.
Still further, it is the object of the present invention to provide a current passing circuit board of a rotary electric machine which can be applied also to a brushless rotary electric machine.
Still further, it is the object of the present invention to provide a current passing circuit board of a rotary electric machine which can be mounted easily to fix on the side of a stator.
Still further, it is the object of the present invention to provide a current passing circuit board of a rotary electric machine in which an independent winding can be wound around each of the tooth of a stator core.